Lauren Dempsey, MS in Biomedicine and Law, RN, FISM News
Researchers from India, Sweden, and Iran were able to restore sight in patients with keratoconus by implanting a bioengineered tissue made from pig skin.
Medical researchers used the tissue, which is made from a collagen protein found in pigs, to replace human patients’ corneas.
The study was published in Nature Biotechnology and detailed how the scientists were able to restore vision by “using an approach that is equally effective, safer, simpler, and more broadly available than donor cornea transplantation.”
In a pilot feasibility study that was conducted in India and Iran, the tissue was implanted in 20 participants with advanced keratoconus to reshape their corneas without removing existing tissue or using sutures.
Keratoconus is a gradual thinning of the cornea that results in a bulging, cone-shaped cornea and impaired vision. The procedure was minimally invasive and researchers noted that during 24 months of follow-up, there were no adverse events.
Fourteen participants were initially blind. However, after receiving an implant, their vision was restored enough to wear glasses or even tolerate contact lenses.
“The results show that it is possible to develop a biomaterial that meets all the criteria for being used as human implants, which can be mass-produced and stored up to two years and thereby reach even more people with vision problems,” said Neil Lagali, co-author of the study and professor at Linkoping University in Sweden. “This gets us around the problem of shortage of donated corneal tissue and access to other treatments for eye diseases.”
It is estimated that 12.7 million people are waiting for a donor cornea, with one cornea available for every 70 needed. While there is increased awareness and encouragement for cornea donations, the shortage is made worse with about 1 million new cases of corneal blindness reported each year.
According to the American Academy of Ophthalmology, the cornea is the clear, front window to the eye that is essential to protecting the eye and to having clear vision. Any damage to the cornea will result in impaired vision or blindness.
The team of scientists was able to create a bioengineered porcine construct, double crosslinked (BPCDX) that was similar to a human cornea, but when implanted had fewer complications and could be more accessible than traditional corneal transplants. Individuals with corneal transplants are at risk for tissue rejection, infection, glaucoma, retinal detachment, and bleeding from the eye. In addition, the bioengineered corneas can be stored for up to two years before use, while donated corneas must be used within two weeks.
The team of researchers found that “following BPCDX implantation, transparency was maintained without degradation, scar formation, adverse reactions or events requiring hospitalization, intensive therapy or further surgical intervention.”
The team is hopeful that the results of this study will improve treatment for the corneal disease as well as other diseases that affect the eyes. The next step for the team will be to conduct a larger clinical trial and seek approval from regulatory agencies before the product can be brought to market and used in healthcare settings.